Method and means of perforating well casing and the like



waiullm ..vv lllnhsvloOOO OOO O 2 Sheets-Sheet 1 Inventor FRAN/f E.ONE/LL B F. E. o'NElLL I Filed Jan. 26, 19:59

lrlllf :Affili METHOD AND MEANS 0F PERFOBATING WELL CASING AND THE LIKEJune 11, 1940.

June ll, 1940. 4 F. E. o'NElLL 2,203,796

METHOD AND MEANS 0F PERFORATING WELL CASING AND THE LIKE Filed Jan. ze,1939 2 sheets-sheet 2 Emmi Ir'ufenor' FRA/wf E. ONE/L1.'

42 i tiorney Patented June l1, 1940 METHOD AND MEANS OF PERFORATING WELLCASING AND THE LIKE Frank E. ONeill, Glendale, Calif., assignor to EdithL. ONeill, Glendaler Calif.

Application January 26, 1939, Serial No. 253,009

6 Claims.

vices and guns which operate underthe force of an explosive charge. Inthe present instance, as

disclosed generally in the above issued patent, I have utilized theabrasive action of a liquid normally found in the well and which whendirected against the surface of a well casing will implnge against thatsurface with sufficient force to erode an opening through the casing andto penetrate the geological formation back of the casing. In theperforation of set well casings a problem always arises if an attempt ismade to perforate the casing in the area where a joint occurs whenlengths of casing are cemented in. In such areas it will be evident thatcontiguous lengths of casing will be in overlapping and telescopedrelation to each other and that between the overlapped faces of thecasing a thickness of cement will occur. This makes it necessary toperforate an inner thickness of metal, an intermediate thicknessofcement and an outer thickness of metal if a perforation is attemptedat such a joint. This operation is very difficult to achieve withmechanical perforating devices but may be accomplished readily by themethod of uid perforation here disclosed.

In perforating an overlapping joint of casing and an intermediatethickness of cement with a liquid under pressure it is necessary topursue a 40 method which will insure that the force of pressure of thejet will not be dissipated within the layer of cement which occursbetween the two walls of pipe since such an action would prevent theouter pipe wall from being perforated. It is 45` the principal object ofthe present invention,

therefore, to provide a method and means of perforating well casing bythe use of a fluid under pressure and in a manner to insure that theperforating jet will penetrate a plurality of layers of casing wall andcementwhereby an opening will be formed completely from the interior ofthe casing to the surrounding bore of the Well.

The present invention contemplates the provision of means whereby anozzle structure will 5o act to direct a jet of liquid under pressureagainst a casing and to interrupt or establish jets of fluid underpressure as the perforating action progresses in a manner to insure thecomplete penetration of a plurality of wall thicknesses.

The invention is illustrated by way of example 5 in the accompanyingdrawings, in which:

Figure 1 is a view in vertical section and elevation disclosing aperforating device set within a well and associated with a fluid pump.

Fig. 2 is anl enlarged view in section showing l0 the lower end of theperforatorand the emergency circulating valve. v

Fig. 3 is an enlarged view in section shown on the line 3--3 of Fig. 1showing the details of construction of a perforating nozzle with whichthe 15 present invention may be accomplished.

` Fig. 4 is a view in transverse section through the perforating nozzleas shown on the line 4 4 4of Fig. 3.

` Fig. 5 is an enlarged fragmentary View show- 20 ing the action of theperforating nozzle and indicating the nozzle structure in anintermediate position. l

Fig. 6 is a view similar to Fig. 5 showing the nozzle structure in itsnal position to complete 25 the perforation.

Fig. 7 is a fragmentary View in section and elevation showing anotherform of the present invention.

Fig. 8 is a fragmentary view in vertical section so and elevationshowing means for moving and adjusting the perforating unit.

Referring more particularly to the drawings,

I0 indicates the mud pump usually used in connection with Well drillingoperations to circulate 35 the drilling fluid. Connected to this pump isa hose II which is attached to the grief stem carried by the swivel headI2. The swivel head is supported from the usual traveling block of thewell rig but is not shown in the drawings. Mounted upon the swivel headis a length of drill pipe I3 which extends downwardly into the well andcarries the perforating structure I4 with which the present invention isconcerned. The perforating structure I4 is here shown as including a 45plurality of cylindrical units I5, the details of `which are shown inFigs. 3 to 6 of the drawings.

At the lower end of this assembled set of units is a set of grippingslips I6 associated with a hook wall spring unit I'I. Below this springunit an 50 emergency circulating valve structure I8 is carried.

Referring particularly to Figs. 3 to 6 of the Y drawings, it will beseen that the units I5 are formed at one end with a threaded pin I9 and55 in this instance extends upwardly into the drill liange 3 I.

tively small jet opening 36.

string and acts as a strainer for the uid which is forced downwardlythrough the string into the various perforating units.

Formed transversely of the body'of each of the perforating units I5 is acylindrical bore 23. This bore is closed at its rear end with a solidthreaded closure 24 and at its forward end with a threaded nozzle plate25. Slidable within the bore is a ring-shaped piston 26. 'I'his pistonis an annular member having a central fluid space 21 therethrough. Astrainer plate 28 is secured to the piston by a threaded nut 29 whichalso holds a packing ring 36 in position. The packing ring 30 isforcedforwardly against an annular The piston ,is free to slide longitudinallyof the bore 23 and is limited in its rearward movement by a sleevebushing 32 which `lines the wall of the bore for a portion of itslength. This bushing 32 is held in position by the closure plate 24. Itwill thus be seen that the forward edge of the sleeve 32,' as indicatedat 33, will limit the rear retracting ,movement of the piston 26 as thepiston is forced away from the nozzle plate 25 by the coil spring 34.

The nozzle plate 25 is here lshown as formed with two jet openingstherethrough, a lower relatively large jet opening 35 and an upper rela-In some instances the nozzle plate may be made with but one jet opening,as will be hereinafter described. The

lower jet opening is formed with a tapered seat 31 at its inner end.'I'he upper jet, opening is substantially of 'the same diameterthroughout its length.

.Mounted upon the piston member 26 is a boss 38 which has an outertapered face 39 from which a pin 40 projects. The pin 4l! is designed toreciprocate through the lower relatively large opening V35 and when ithas moyed outwardly withthe piston to the length of its stroke thetapered face 39 on the boss 38 will engage and seat against the taperedseat 31 of the opening. This will seal the opening 35, and since theopenings 35 and 36 are both in communication with the supply of liquidunder pressure within the bore 23, the fluid will then exit through theopeningv 36 only. By this arrangement a lower perforation 4I will be cutthrough the wall of the inner casing section 42, after Which a jet offluid from the upper opening 36 will cut a perforation forating unit.-Mounted along the outer face of the conical portion is a plurality ofgripping Slips 48 having teeth which will bite into the wall of thecasing 42. These slips are suitably supported upon yieldable arms 49 andare carried upon a 'collar 50 of the spring basket structure I1. The

spring basket structure is of the usual hook wall type commonlyassociated with casing packers and includes a plurality of spring bows 5I, which may be flexed outwardly to frictionally hold the basket inposition Within the casing while permitting the conical member 41 tomove downwardly and force the slips 48y outwardly against the casingwall. A usual bayonet slot 52 and pin 53 cooperate to hold the hook wallsprings in their unflexed position until it is desired to set thestructure in a well. The mandrel 46 extends downwardly through thestructure l1 and engages a sub 54 which carries a ball seat 55. A lowersub 56 is threaded to the ball seat and carries a nosepiece 51 whichacts to guide the drill string and perforatingv structure down the hole.The 'mandrel 46 is tubular. The sub 56 has a central passageway 58therethrough which is in communication with a passageway 59 in the sub56. A plurality of radial openings 60 extend from the passageway 59. Bythis structure an emergency circulation of fluid can be produced fromwithin the casing,` then upwardly through the passageway 58 which issealed against downward ow of liquid by acheck ball 6I. The uid may thenow upwardly into the mandrel and through the perforating device to thedrill string since the various transverse bores 23 of the perforatingunits are in communication through passageways 62.

Referring particularly to Fig. '7 of the. drawings, it is seen that thenozzle plate 25 will be shown as there formed with opening 36 and noother opening.

As previously stated, the purpose of this invention is to provide amethod and meansv of perforating a plurality of spaced casing wallsbetween which material, such as concrete, occurs.

In the form of theinvention shown in Fig. '1 of the drawings the nozzleplate 25 is formed with a single opening. 'I'his opening provides a jetof fluid under pressure as indicated at 64. The perforating structure isset at a lower position than indicated in Fig. 7, -uring which time aninitial perforation 4I is cut through the inner casing wall 42. It hasbeenfound, however, that in view of the presence ofv cementitiousmaterial between the casing walls 42 and 45 the action of the jet offluid after cutting the opening 4I is decreased and the force of thecutting liquid is dissipated in the material representing the layer 44and particularly for the reason that the spent liquid must force its wayback out through the opening 4I and against the inflowing jet of liquid.

The result is that the outer casing wall 45 is not Y penetrated'. When,however, the perforating structure is raised so that the opening 36 isat another level a second perforation will be made as indicated at 65.As the cutting action con- -tinues through the intermediate layer 44this intermediate material will be channeled, as indicated at 66, sothat it may flow out through the previously cut opening 4I. Thus thespent liquid will not offer resistance to the inflowingjet of liquid andwill result in cutting through the back wall 45, as indicated at 61.

It is to be understood that various means may be provided for moving theperforating structure to set the jet openings at a suitable level toproduce a second perforation. A form of set structure has been shown inFig. 8, which comprises a sleeve 68 secured to the drill string I3 andhaving within it a threaded portion 39. Extending upwardly into thesleeve is a threaded mandre] Ill which is rigidly secured to theperforating unit- I4 and projects upwardly therefrom. The threadedmandrel is tubular to permit circulation of fluid therethrough and isprovided with suitablepacking 'H and 'i2 to prevent leakage.

that a second perforation may be cut in the pipe.

In order that the method shown and described with reference to Fig. 7may be carried out with greater accuracy and so that the perforation maybe completed at one setting of the tool, meansare provided, as shown inFigs. 1 to 6 of the drawings, for automatically diverting the stream ofcutting liquid from perforation 4I when it has been completed. This isaccomplished in the present instance by the action of the pin 40. Whenthis particular structure is used the perforating tool may be set in thewell and manipulated so that the slips 48 will grip the side wall.

It is to be understood that while the nozzle plate 25 is here shown asbeing arranged with the nozzle opening 35 beneath the nozzle opening 36it is possible to reverse this arrangement or to dispose the nozzleopenings in a plane atany angle to the horizontal or in a plane lyinghorizontally so that the openings would be side by side.

By way of example the operation of the invention will be described asshown in the drawings, where it will be seen that the device may belowered into the well, after which the slip structure is set to placethe perforating tool with relation to the casing. Fluid is forced downthe drill string from the pump IIJ, this fluid being drilling fluidwhich contains a normal proportion of abrasive material, or if desiredmay be so'me special liquid. Fluid passes through the perforations inthe perforated nipple 22 and then down through the various perforatingunits I5, where it will flow through the passageway 62 into thetransverse bores 23, and will at the same time flow on down the nextsucceeding units through the passageway 62. While the liquid is withinthe different bores 23 a sufficient pressure will be created to forcethe piston element 26 of each bore outwardly and away from its seat 33.This will tend to compress the spring 34. At the same time the liquidwill pass through the central opening 21 of the piston regardless ofwhether or not the strainer 28 is in place. The liquid which passesthrough the center opening 21 of the piston is under pressure and in theinitial stages of the operation of this device liquid will flow out ofthe relatively large nozzle opening 35 and the relatively small nozzleopening 33 and will flow along and around the pin 40. The force of thepressure against the piston will move the pin 40 so that its outer endabuts against the surface of the casing wall 42. Abrasive action willthen takeplace around the pin 40 and upon the casing wall so that anopening 4l will be cut eventually. When this takes place the material ofthe intermediate layer 44 will rapidly make way for the end of the pin40 until the conical portion 39 of the boss 38 abuts against the taperedseat 31 at the back of the nozzle opening 35. This will interrupt theflow of cutting liquid through the nozzle opening 35 and will cause theentire pressure of the liquid to be exerted upon the jet 34 passingoutwardly through the nozzle opening 36. The jet will then cut theopening 43 in the plate 42 and will penetrate the intermediate layer 44,after which it will channel out, as indicated at 'i6 and permit thespent fluid to move away from the jet and the cutting area while a nalopening "I3 is cut in the outer casing wall 45. It will thus be seenthat by the method and means here shown it is possible to perforate aplurality of layers of material having different cutting characteristicsby an abrasive cutting action such as produced by the impingement of astream of liquid against the surface to be penetrated.

While I have shownthe preferred form of my method and means of carryingout my invention, it will be understood that various changes may be madein the combination, construction and arrangement of parts by thoseskilled in the art, without departing from the spirit of my invention asclaimed.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

l. A method of perforating a laminated member with an abrasive uid underpressure, which comprises directing a jet of said fluid through thesurface lamina while forming a perforation therewith and directing a jetof said lluid through said surface lamina at a point adjacent to thepoint of said first perforation whereby the spent luid will be relievedfrom the perforating area through the flrst perforation until the secondperforation has been formed entirely through the member. 2. A method ofperforating a laminated member comprising hard laminae and anintermediate relatively soft lamina with an abrasive uid under pressurewhich comprises directing a jet of said fluid through the hard surfacelamina while forming a perforation and directing a jet of said fluidthrough said hard surface lamina at a point adjacent to the point ofsaid rst perforation whereby the spent fluid will be relieved from theperforating area through the first perforation until the secondperforation has been formed entirely through the member.

3. A method of perforating well casing including telescoping casingsections with an intermediate layer of cement, which method comprisesprojecting a jet of abrasive uid under pressure against the surface ofone casing section until said wall has been penetrated, then projectinga jet of uid through the surface of the said casing section and throughthe intermediate layer of cement and the outer casing section whilepermitting the spent fluid to be relieved from the perforating areathrough the rst perforated section.

4. A tool for perforating well casing which comprises a body memberadapted to be lowered into a well as supported by a string of pipe, alaterally disposed discharge chamber within the body member and incommunication with a string of pipe whereby fluid under pressure may beconducted thereto, a nozzle platev at the outer end of said chamberhaving a pair of jet openings therethrough, a movable member extendingthrough one of said jet openings and adapted to contact the casing to beperforated, pressure actuated means within the chamber carrying themovable member and forcing it outwardly, and cooperating valve means onthe nozzle plate and the movable member whereby when the movable memberhas advanced a predetermined distance said valve means will close tocause the fluid to pass outwardly through the other nozzle opening only.

5. A tool for perforating Well casing which comprises a body memberadapted to be lowered into a well as supported by a string of pipe, alaterally disposed discharge chamber withinA the body member and incommunication with a string of pipe whereby fluid under pressure may beconducted thereto, a nozzle plate at the outer end of said chamberhaving a pair of jet openings therethrough, a movable member extendingthrough one of said jet openings and adapted to contact the casing to beperforated, pressure actuated means within the chamber carrying themovable member and forcing it outwardly, cooperating valve means on thenozzle plate and the movable member whereby when the movable member hasadvanced a predetermined distance said valve means will rclose to causethe uid to pass outwardly through the other nozzle opening only, andmeans associated with the structure for holding the body member in a setposition with relation to the casing.

6. A perforating device through which an abrasive uid under pressure isdelivered, a jet opening therefrom through which a jet of said uid maybe directed against an object to be perforated, a second jet openingthrough which a jet of said abrasive uid may be directed against theobject to be perforated, and means acting automatically to interrupt aow of uid through the rst jet opening when a predetermined depth ofopening has been formed.

. FRANK E. ONEILL.

